1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 *  Routines for control of EMU10K1 MPU-401 in UART mode
5 */
6
7#include <linux/time.h>
8#include <linux/init.h>
9#include <sound/core.h>
10#include <sound/emu10k1.h>
11
12#define EMU10K1_MIDI_MODE_INPUT		(1<<0)
13#define EMU10K1_MIDI_MODE_OUTPUT	(1<<1)
14
15static inline unsigned char mpu401_read(struct snd_emu10k1 *emu,
16					struct snd_emu10k1_midi *mpu, int idx)
17{
18	if (emu->audigy)
19		return (unsigned char)snd_emu10k1_ptr_read(emu, mpu->port + idx, 0);
20	else
21		return inb(emu->port + mpu->port + idx);
22}
23
24static inline void mpu401_write(struct snd_emu10k1 *emu,
25				struct snd_emu10k1_midi *mpu, int data, int idx)
26{
27	if (emu->audigy)
28		snd_emu10k1_ptr_write(emu, mpu->port + idx, 0, data);
29	else
30		outb(data, emu->port + mpu->port + idx);
31}
32
33#define mpu401_write_data(emu, mpu, data)	mpu401_write(emu, mpu, data, 0)
34#define mpu401_write_cmd(emu, mpu, data)	mpu401_write(emu, mpu, data, 1)
35#define mpu401_read_data(emu, mpu)		mpu401_read(emu, mpu, 0)
36#define mpu401_read_stat(emu, mpu)		mpu401_read(emu, mpu, 1)
37
38#define mpu401_input_avail(emu,mpu)	(!(mpu401_read_stat(emu,mpu) & 0x80))
39#define mpu401_output_ready(emu,mpu)	(!(mpu401_read_stat(emu,mpu) & 0x40))
40
41#define MPU401_RESET		0xff
42#define MPU401_ENTER_UART	0x3f
43#define MPU401_ACK		0xfe
44
45static void mpu401_clear_rx(struct snd_emu10k1 *emu, struct snd_emu10k1_midi *mpu)
46{
47	int timeout = 100000;
48	for (; timeout > 0 && mpu401_input_avail(emu, mpu); timeout--)
49		mpu401_read_data(emu, mpu);
50#ifdef CONFIG_SND_DEBUG
51	if (timeout <= 0)
52		dev_err(emu->card->dev,
53			"cmd: clear rx timeout (status = 0x%x)\n",
54			mpu401_read_stat(emu, mpu));
55#endif
56}
57
58/*
59
60 */
61
62static void do_emu10k1_midi_interrupt(struct snd_emu10k1 *emu, struct snd_emu10k1_midi *midi, unsigned int status)
63{
64	unsigned char byte;
65
66	if (midi->rmidi == NULL) {
67		snd_emu10k1_intr_disable(emu, midi->tx_enable | midi->rx_enable);
68		return;
69	}
70
71	spin_lock(&midi->input_lock);
72	if ((status & midi->ipr_rx) && mpu401_input_avail(emu, midi)) {
73		if (!(midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)) {
74			mpu401_clear_rx(emu, midi);
75		} else {
76			byte = mpu401_read_data(emu, midi);
77			if (midi->substream_input)
78				snd_rawmidi_receive(midi->substream_input, &byte, 1);
79		}
80	}
81	spin_unlock(&midi->input_lock);
82
83	spin_lock(&midi->output_lock);
84	if ((status & midi->ipr_tx) && mpu401_output_ready(emu, midi)) {
85		if (midi->substream_output &&
86		    snd_rawmidi_transmit(midi->substream_output, &byte, 1) == 1) {
87			mpu401_write_data(emu, midi, byte);
88		} else {
89			snd_emu10k1_intr_disable(emu, midi->tx_enable);
90		}
91	}
92	spin_unlock(&midi->output_lock);
93}
94
95static void snd_emu10k1_midi_interrupt(struct snd_emu10k1 *emu, unsigned int status)
96{
97	do_emu10k1_midi_interrupt(emu, &emu->midi, status);
98}
99
100static void snd_emu10k1_midi_interrupt2(struct snd_emu10k1 *emu, unsigned int status)
101{
102	do_emu10k1_midi_interrupt(emu, &emu->midi2, status);
103}
104
105static int snd_emu10k1_midi_cmd(struct snd_emu10k1 * emu, struct snd_emu10k1_midi *midi, unsigned char cmd, int ack)
106{
107	int timeout, ok;
108
109	spin_lock_irq(&midi->input_lock);
110	mpu401_write_data(emu, midi, 0x00);
111	/* mpu401_clear_rx(emu, midi); */
112
113	mpu401_write_cmd(emu, midi, cmd);
114	if (ack) {
115		ok = 0;
116		timeout = 10000;
117		while (!ok && timeout-- > 0) {
118			if (mpu401_input_avail(emu, midi)) {
119				if (mpu401_read_data(emu, midi) == MPU401_ACK)
120					ok = 1;
121			}
122		}
123		if (!ok && mpu401_read_data(emu, midi) == MPU401_ACK)
124			ok = 1;
125	} else {
126		ok = 1;
127	}
128	spin_unlock_irq(&midi->input_lock);
129	if (!ok) {
130		dev_err(emu->card->dev,
131			"midi_cmd: 0x%x failed at 0x%lx (status = 0x%x, data = 0x%x)!!!\n",
132			   cmd, emu->port,
133			   mpu401_read_stat(emu, midi),
134			   mpu401_read_data(emu, midi));
135		return 1;
136	}
137	return 0;
138}
139
140static int snd_emu10k1_midi_input_open(struct snd_rawmidi_substream *substream)
141{
142	struct snd_emu10k1 *emu;
143	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
144
145	emu = midi->emu;
146	if (snd_BUG_ON(!emu))
147		return -ENXIO;
148	spin_lock_irq(&midi->open_lock);
149	midi->midi_mode |= EMU10K1_MIDI_MODE_INPUT;
150	midi->substream_input = substream;
151	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT)) {
152		spin_unlock_irq(&midi->open_lock);
153		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 1))
154			goto error_out;
155		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_ENTER_UART, 1))
156			goto error_out;
157	} else {
158		spin_unlock_irq(&midi->open_lock);
159	}
160	return 0;
161
162error_out:
163	return -EIO;
164}
165
166static int snd_emu10k1_midi_output_open(struct snd_rawmidi_substream *substream)
167{
168	struct snd_emu10k1 *emu;
169	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
170
171	emu = midi->emu;
172	if (snd_BUG_ON(!emu))
173		return -ENXIO;
174	spin_lock_irq(&midi->open_lock);
175	midi->midi_mode |= EMU10K1_MIDI_MODE_OUTPUT;
176	midi->substream_output = substream;
177	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)) {
178		spin_unlock_irq(&midi->open_lock);
179		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 1))
180			goto error_out;
181		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_ENTER_UART, 1))
182			goto error_out;
183	} else {
184		spin_unlock_irq(&midi->open_lock);
185	}
186	return 0;
187
188error_out:
189	return -EIO;
190}
191
192static int snd_emu10k1_midi_input_close(struct snd_rawmidi_substream *substream)
193{
194	struct snd_emu10k1 *emu;
195	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
196	int err = 0;
197
198	emu = midi->emu;
199	if (snd_BUG_ON(!emu))
200		return -ENXIO;
201	spin_lock_irq(&midi->open_lock);
202	snd_emu10k1_intr_disable(emu, midi->rx_enable);
203	midi->midi_mode &= ~EMU10K1_MIDI_MODE_INPUT;
204	midi->substream_input = NULL;
205	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT)) {
206		spin_unlock_irq(&midi->open_lock);
207		err = snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 0);
208	} else {
209		spin_unlock_irq(&midi->open_lock);
210	}
211	return err;
212}
213
214static int snd_emu10k1_midi_output_close(struct snd_rawmidi_substream *substream)
215{
216	struct snd_emu10k1 *emu;
217	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
218	int err = 0;
219
220	emu = midi->emu;
221	if (snd_BUG_ON(!emu))
222		return -ENXIO;
223	spin_lock_irq(&midi->open_lock);
224	snd_emu10k1_intr_disable(emu, midi->tx_enable);
225	midi->midi_mode &= ~EMU10K1_MIDI_MODE_OUTPUT;
226	midi->substream_output = NULL;
227	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)) {
228		spin_unlock_irq(&midi->open_lock);
229		err = snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 0);
230	} else {
231		spin_unlock_irq(&midi->open_lock);
232	}
233	return err;
234}
235
236static void snd_emu10k1_midi_input_trigger(struct snd_rawmidi_substream *substream, int up)
237{
238	struct snd_emu10k1 *emu;
239	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
240	emu = midi->emu;
241	if (snd_BUG_ON(!emu))
242		return;
243
244	if (up)
245		snd_emu10k1_intr_enable(emu, midi->rx_enable);
246	else
247		snd_emu10k1_intr_disable(emu, midi->rx_enable);
248}
249
250static void snd_emu10k1_midi_output_trigger(struct snd_rawmidi_substream *substream, int up)
251{
252	struct snd_emu10k1 *emu;
253	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
254
255	emu = midi->emu;
256	if (snd_BUG_ON(!emu))
257		return;
258
259	if (up) {
260		int max = 4;
261		unsigned char byte;
262
263		/* try to send some amount of bytes here before interrupts */
264		spin_lock_irq(&midi->output_lock);
265		while (max > 0) {
266			if (mpu401_output_ready(emu, midi)) {
267				if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT) ||
268				    snd_rawmidi_transmit(substream, &byte, 1) != 1) {
269					/* no more data */
270					spin_unlock_irq(&midi->output_lock);
271					return;
272				}
273				mpu401_write_data(emu, midi, byte);
274				max--;
275			} else {
276				break;
277			}
278		}
279		spin_unlock_irq(&midi->output_lock);
280		snd_emu10k1_intr_enable(emu, midi->tx_enable);
281	} else {
282		snd_emu10k1_intr_disable(emu, midi->tx_enable);
283	}
284}
285
286/*
287
288 */
289
290static const struct snd_rawmidi_ops snd_emu10k1_midi_output =
291{
292	.open =		snd_emu10k1_midi_output_open,
293	.close =	snd_emu10k1_midi_output_close,
294	.trigger =	snd_emu10k1_midi_output_trigger,
295};
296
297static const struct snd_rawmidi_ops snd_emu10k1_midi_input =
298{
299	.open =		snd_emu10k1_midi_input_open,
300	.close =	snd_emu10k1_midi_input_close,
301	.trigger =	snd_emu10k1_midi_input_trigger,
302};
303
304static void snd_emu10k1_midi_free(struct snd_rawmidi *rmidi)
305{
306	struct snd_emu10k1_midi *midi = rmidi->private_data;
307	midi->interrupt = NULL;
308	midi->rmidi = NULL;
309}
310
311static int emu10k1_midi_init(struct snd_emu10k1 *emu, struct snd_emu10k1_midi *midi, int device, char *name)
312{
313	struct snd_rawmidi *rmidi;
314	int err;
315
316	err = snd_rawmidi_new(emu->card, name, device, 1, 1, &rmidi);
317	if (err < 0)
318		return err;
319	midi->emu = emu;
320	spin_lock_init(&midi->open_lock);
321	spin_lock_init(&midi->input_lock);
322	spin_lock_init(&midi->output_lock);
323	strcpy(rmidi->name, name);
324	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_emu10k1_midi_output);
325	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_emu10k1_midi_input);
326	rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT |
327	                     SNDRV_RAWMIDI_INFO_INPUT |
328	                     SNDRV_RAWMIDI_INFO_DUPLEX;
329	rmidi->private_data = midi;
330	rmidi->private_free = snd_emu10k1_midi_free;
331	midi->rmidi = rmidi;
332	return 0;
333}
334
335int snd_emu10k1_midi(struct snd_emu10k1 *emu)
336{
337	struct snd_emu10k1_midi *midi = &emu->midi;
338	int err;
339
340	err = emu10k1_midi_init(emu, midi, 0, "EMU10K1 MPU-401 (UART)");
341	if (err < 0)
342		return err;
343
344	midi->tx_enable = INTE_MIDITXENABLE;
345	midi->rx_enable = INTE_MIDIRXENABLE;
346	midi->port = MUDATA;
347	midi->ipr_tx = IPR_MIDITRANSBUFEMPTY;
348	midi->ipr_rx = IPR_MIDIRECVBUFEMPTY;
349	midi->interrupt = snd_emu10k1_midi_interrupt;
350	return 0;
351}
352
353int snd_emu10k1_audigy_midi(struct snd_emu10k1 *emu)
354{
355	struct snd_emu10k1_midi *midi;
356	int err;
357
358	midi = &emu->midi;
359	err = emu10k1_midi_init(emu, midi, 0, "Audigy MPU-401 (UART)");
360	if (err < 0)
361		return err;
362
363	midi->tx_enable = INTE_MIDITXENABLE;
364	midi->rx_enable = INTE_MIDIRXENABLE;
365	midi->port = A_MUDATA1;
366	midi->ipr_tx = IPR_MIDITRANSBUFEMPTY;
367	midi->ipr_rx = IPR_MIDIRECVBUFEMPTY;
368	midi->interrupt = snd_emu10k1_midi_interrupt;
369
370	midi = &emu->midi2;
371	err = emu10k1_midi_init(emu, midi, 1, "Audigy MPU-401 #2");
372	if (err < 0)
373		return err;
374
375	midi->tx_enable = INTE_A_MIDITXENABLE2;
376	midi->rx_enable = INTE_A_MIDIRXENABLE2;
377	midi->port = A_MUDATA2;
378	midi->ipr_tx = IPR_A_MIDITRANSBUFEMPTY2;
379	midi->ipr_rx = IPR_A_MIDIRECVBUFEMPTY2;
380	midi->interrupt = snd_emu10k1_midi_interrupt2;
381	return 0;
382}
383